Equity-Based Compensation - Activity Related to Plans (Details) $ in Millions	1 Months Ended	3 Months Ended
	Feb. 28, 2017 USD ($) shares	Mar. 31, 2017 plan shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of equity compensation plans | plan		4
Performance Restricted Stock Units (RSUs) | 2007 Equity Plan
Restricted Stock Units
Granted (in shares)	191,250
Award vesting period (in years)	3 years
Fair value, performance- based RSUs | $	$ 5.7
Compensation expense, period for recognition (in years)	3 years
Stock Options
Stock Options
Outstanding at beginning of period (in shares)		3,113,178
Granted (in shares)		322,210
Exercised (in shares)		(9,065)
Expired or terminated (in shares)		(78,602)
Outstanding at end of period (in shares)		3,347,721
Stock Options | 2007 Equity Plan
Stock Options
Outstanding at beginning of period (in shares)		2,158,822
Granted (in shares)		322,210
Exercised (in shares)		(9,065)
Expired or terminated (in shares)		(50,696)
Outstanding at end of period (in shares)		2,421,271
Stock Options | 2000 Equity Plan
Stock Options
Outstanding at beginning of period (in shares)		5,200
Granted (in shares)		0
Exercised (in shares)		0
Expired or terminated (in shares)		0
Outstanding at end of period (in shares)		5,200
Stock Options | 2013 Lumara Equity Plan
Stock Options
Outstanding at beginning of period (in shares)		134,181
Granted (in shares)		0
Exercised (in shares)		0
Expired or terminated (in shares)		(281)
Outstanding at end of period (in shares)		133,900
Stock Options | Inducement Grants
Stock Options
Outstanding at beginning of period (in shares)		814,975
Granted (in shares)		0
Exercised (in shares)		0
Expired or terminated (in shares)		(27,625)
Outstanding at end of period (in shares)		787,350
Restricted Stock Units
Restricted Stock Units
Outstanding at beginning of year (in shares)		936,954
Granted (in shares)		732,956
Vested (in shares)		(155,720)
Expired or terminated (in shares)		(32,776)
Outstanding at end of year (in shares)		1,481,414
Restricted Stock Units | 2007 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (in shares)		773,804
Granted (in shares)		732,956
Vested (in shares)		(143,056)
Expired or terminated (in shares)		(26,957)
Outstanding at end of year (in shares)		1,336,747
Restricted Stock Units | 2000 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (in shares)		0
Granted (in shares)		0
Vested (in shares)		0
Expired or terminated (in shares)		0
Outstanding at end of year (in shares)		0
Restricted Stock Units | 2013 Lumara Equity Plan
Restricted Stock Units
Outstanding at beginning of year (in shares)		27,694
Granted (in shares)		0
Vested (in shares)		(11,664)
Expired or terminated (in shares)		(501)
Outstanding at end of year (in shares)		15,529
Restricted Stock Units | Inducement Grants
Restricted Stock Units
Outstanding at beginning of year (in shares)		135,456
Granted (in shares)		0
Vested (in shares)		(1,000)
Expired or terminated (in shares)		(5,318)
Outstanding at end of year (in shares)		129,138